*/
#include "isl_map_private.h"
-#include "isl_seq.h"
+#include <isl/seq.h>
#include "isl_tab.h"
+#include <isl_mat_private.h>
#define STATUS_ERROR -1
#define STATUS_REDUNDANT 1
}
}
-/* Given a pair of basic maps i and j such that j stick out
+/* Given a pair of basic maps i and j such that j sticks out
* of i at n cut constraints, each time by at most one,
* try to compute wrapping constraints and replace the two
* basic maps by a single basic map.
* wrapped around their ridges, except those ridges determined
* by any of the other cut constraints.
* The intersections of cut constraints need to be ignored
- * as the result of wrapping on cur constraint around another
+ * as the result of wrapping one cut constraint around another
* would result in a constraint cutting the union.
* In each case, the facets are wrapped to include the union
* of the two basic maps.
return -1;
}
-/* Given two basic sets i and j such that i has not cut equalities,
+/* Given two basic sets i and j such that i has no cut equalities,
* check if relaxing all the cut inequalities of i by one turns
* them into valid constraint for j and check if we can wrap in
* the bits that are sticking out.
return changed;
}
+/* The two basic maps lie on adjacent hyperplanes. In particular,
+ * basic map "i" has an equality that lies parallel to basic map "j".
+ * Check if we can wrap the facets around the parallel hyperplanes
+ * to include the other set.
+ *
+ * We perform basically the same operations as can_wrap_in_facet,
+ * except that we don't need to select a facet of one of the sets.
+ * _
+ * \\ \\
+ * \\ => \\
+ * \ \|
+ *
+ * We only allow one equality of "i" to be adjacent to an equality of "j"
+ * to avoid coalescing
+ *
+ * [m, n] -> { [x, y] -> [x, 1 + y] : x >= 1 and y >= 1 and
+ * x <= 10 and y <= 10;
+ * [x, y] -> [1 + x, y] : x >= 1 and x <= 20 and
+ * y >= 5 and y <= 15 }
+ *
+ * to
+ *
+ * [m, n] -> { [x, y] -> [x2, y2] : x >= 1 and 10y2 <= 20 - x + 10y and
+ * 4y2 >= 5 + 3y and 5y2 <= 15 + 4y and
+ * y2 <= 1 + x + y - x2 and y2 >= y and
+ * y2 >= 1 + x + y - x2 }
+ */
+static int check_eq_adj_eq(struct isl_map *map, int i, int j,
+ struct isl_tab **tabs, int *eq_i, int *ineq_i, int *eq_j, int *ineq_j)
+{
+ int k;
+ int changed = 0;
+ struct isl_mat *wraps = NULL;
+ struct isl_set *set_i = NULL;
+ struct isl_set *set_j = NULL;
+ struct isl_vec *bound = NULL;
+ unsigned total = isl_basic_map_total_dim(map->p[i]);
+
+ if (count(eq_i, 2 * map->p[i]->n_eq, STATUS_ADJ_EQ) != 1)
+ return 0;
+
+ for (k = 0; k < 2 * map->p[i]->n_eq ; ++k)
+ if (eq_i[k] == STATUS_ADJ_EQ)
+ break;
+
+ set_i = set_from_updated_bmap(map->p[i], tabs[i]);
+ set_j = set_from_updated_bmap(map->p[j], tabs[j]);
+ wraps = isl_mat_alloc(map->ctx, 2 * (map->p[i]->n_eq + map->p[j]->n_eq) +
+ map->p[i]->n_ineq + map->p[j]->n_ineq,
+ 1 + total);
+ bound = isl_vec_alloc(map->ctx, 1 + total);
+ if (!set_i || !set_j || !wraps || !bound)
+ goto error;
+
+ if (k % 2 == 0)
+ isl_seq_neg(bound->el, map->p[i]->eq[k / 2], 1 + total);
+ else
+ isl_seq_cpy(bound->el, map->p[i]->eq[k / 2], 1 + total);
+ isl_int_add_ui(bound->el[0], bound->el[0], 1);
+
+ isl_seq_cpy(wraps->row[0], bound->el, 1 + total);
+ wraps->n_row = 1;
+
+ if (add_wraps(wraps, map->p[j], tabs[j], bound->el, set_i) < 0)
+ goto error;
+ if (!wraps->n_row)
+ goto unbounded;
+
+ isl_int_sub_ui(bound->el[0], bound->el[0], 1);
+ isl_seq_neg(bound->el, bound->el, 1 + total);
+
+ isl_seq_cpy(wraps->row[wraps->n_row], bound->el, 1 + total);
+ wraps->n_row++;
+
+ if (add_wraps(wraps, map->p[i], tabs[i], bound->el, set_j) < 0)
+ goto error;
+ if (!wraps->n_row)
+ goto unbounded;
+
+ changed = fuse(map, i, j, tabs, eq_i, ineq_i, eq_j, ineq_j, wraps);
+
+ if (0) {
+error: changed = -1;
+ }
+unbounded:
+
+ isl_mat_free(wraps);
+ isl_set_free(set_i);
+ isl_set_free(set_j);
+ isl_vec_free(bound);
+
+ return changed;
+}
+
/* Check if the union of the given pair of basic maps
* can be represented by a single basic map.
* If so, replace the pair by the single basic map and return 1.
* adj_ineq the given constraint is adjacent (on the outside)
* to an inequality of the other basic map
*
- * We consider six cases in which we can replace the pair by a single
+ * We consider seven cases in which we can replace the pair by a single
* basic map. We ignore all "redundant" constraints.
*
* 1. all constraints of one basic map are valid
* Moreover, the facets corresponding to the cut constraints and
* the pieces of the other basic map at offset one from these cut
* constraints can be wrapped around their ridges to include
- * the unione of the two basic maps
+ * the union of the two basic maps
* => the pair can be replaced by a basic map consisting
* of the valid constraints in both basic maps together
* with all wrapping constraints
*
+ * 7. the two basic maps live in adjacent hyperplanes. In principle
+ * such sets can always be combined through wrapping, but we impose
+ * that there is only one such pair, to avoid overeager coalescing.
+ *
* Throughout the computation, we maintain a collection of tableaus
* corresponding to the basic maps. When the basic maps are dropped
* or combined, the tableaus are modified accordingly.
int *ineq_j = NULL;
eq_i = eq_status_in(map, i, j, tabs);
+ if (!eq_i)
+ goto error;
if (any(eq_i, 2 * map->p[i]->n_eq, STATUS_ERROR))
goto error;
if (any(eq_i, 2 * map->p[i]->n_eq, STATUS_SEPARATE))
goto done;
eq_j = eq_status_in(map, j, i, tabs);
+ if (!eq_j)
+ goto error;
if (any(eq_j, 2 * map->p[j]->n_eq, STATUS_ERROR))
goto error;
if (any(eq_j, 2 * map->p[j]->n_eq, STATUS_SEPARATE))
goto done;
ineq_i = ineq_status_in(map, i, j, tabs);
+ if (!ineq_i)
+ goto error;
if (any(ineq_i, map->p[i]->n_ineq, STATUS_ERROR))
goto error;
if (any(ineq_i, map->p[i]->n_ineq, STATUS_SEPARATE))
goto done;
ineq_j = ineq_status_in(map, j, i, tabs);
+ if (!ineq_j)
+ goto error;
if (any(ineq_j, map->p[j]->n_ineq, STATUS_ERROR))
goto error;
if (any(ineq_j, map->p[j]->n_ineq, STATUS_SEPARATE))
all(ineq_j, map->p[j]->n_ineq, STATUS_VALID)) {
drop(map, i, tabs);
changed = 1;
- } else if (any(eq_i, 2 * map->p[i]->n_eq, STATUS_ADJ_EQ) ||
- any(eq_j, 2 * map->p[j]->n_eq, STATUS_ADJ_EQ)) {
- /* ADJ EQ PAIR */
+ } else if (any(eq_i, 2 * map->p[i]->n_eq, STATUS_ADJ_EQ)) {
+ changed = check_eq_adj_eq(map, i, j, tabs,
+ eq_i, ineq_i, eq_j, ineq_j);
+ } else if (any(eq_j, 2 * map->p[j]->n_eq, STATUS_ADJ_EQ)) {
+ changed = check_eq_adj_eq(map, j, i, tabs,
+ eq_j, ineq_j, eq_i, ineq_i);
} else if (any(eq_i, 2 * map->p[i]->n_eq, STATUS_ADJ_INEQ) ||
any(eq_j, 2 * map->p[j]->n_eq, STATUS_ADJ_INEQ)) {
changed = check_adj_eq(map, i, j, tabs,